diff --git a/lib/yunq/serialize.cpp b/lib/yunq/serialize.cpp
index 6522ab3..188685a 100644
--- a/lib/yunq/serialize.cpp
+++ b/lib/yunq/serialize.cpp
@@ -14,6 +14,12 @@ void Serializer::WriteHeader() {
   buffer_.WriteAt<uint32_t>(offset_ + 12, 0);  // TODO: Calculate CRC32.
 }
 
+template <>
+void Serializer::WriteField<uint64_t>(uint64_t field_index,
+                                      const uint64_t& value) {
+  buffer_.WriteAt<uint64_t>(field_offset(field_index), value);
+}
+
 template <>
 void Serializer::WriteField<glcr::String>(uint64_t field_index,
                                           const glcr::String& value) {
@@ -29,6 +35,23 @@ void Serializer::WriteField<glcr::String>(uint64_t field_index,
   buffer_.WriteAt<ExtensionPointer>(field_offset(field_index), ptr);
 }
 
+template <>
+void Serializer::WriteRepeated<uint64_t>(uint64_t field_index,
+                                         const glcr::Vector<uint64_t>& value) {
+  ExtensionPointer ptr{
+      .offset = (uint32_t)next_extension_,
+      .length = (uint32_t)(value.size() * sizeof(uint64_t)),
+  };
+
+  next_extension_ += ptr.length;
+  buffer_.WriteAt<ExtensionPointer>(field_offset(field_index), ptr);
+
+  for (uint64_t i = 0; i < value.size(); i++) {
+    uint32_t ext_offset = offset_ + ptr.offset + (i * sizeof(uint64_t));
+    buffer_.WriteAt<uint64_t>(ext_offset, value.at(i));
+  }
+}
+
 void Serializer::WriteCapability(uint64_t field_index, uint64_t value) {
   if (caps_) {
     buffer_.WriteAt<uint64_t>(field_offset(field_index), next_cap_);
diff --git a/lib/yunq/serialize.h b/lib/yunq/serialize.h
index ae6a77b..68f9775 100644
--- a/lib/yunq/serialize.h
+++ b/lib/yunq/serialize.h
@@ -55,30 +55,16 @@ class Serializer {
   }
 };
 
-template <typename T>
-void Serializer::WriteField(uint64_t field_index, const T& value) {
-  buffer_.WriteAt<T>(field_offset(field_index), value);
-}
+template <>
+void Serializer::WriteField<uint64_t>(uint64_t field_index,
+                                      const uint64_t& value);
 
 template <>
 void Serializer::WriteField<glcr::String>(uint64_t field_index,
                                           const glcr::String& value);
 
-template <typename T>
-void Serializer::WriteRepeated(uint64_t field_index,
-                               const glcr::Vector<T>& value) {
-  ExtensionPointer ptr{
-      .offset = (uint32_t)next_extension_,
-      .length = (uint32_t)(value.size() * sizeof(T)),
-  };
-
-  next_extension_ += ptr.length;
-  buffer_.WriteAt<ExtensionPointer>(field_offset(field_index), ptr);
-
-  for (uint64_t i = 0; i < value.size(); i++) {
-    uint32_t ext_offset = offset_ + ptr.offset + (i * sizeof(T));
-    buffer_.WriteAt<T>(ext_offset, value.at(i));
-  }
-}
+template <>
+void Serializer::WriteRepeated<uint64_t>(uint64_t field_index,
+                                         const glcr::Vector<uint64_t>& value);
 
 }  // namespace yunq